RADULA 159 
Light- "greem slender, creeping, becoming intricately caespitose: 
stems 1—2 cm. long, pinnately or somewhat bipinnately branched, 
the branches mostly short: leaves contiguous or laxly imbricate, 
patent or erecto-patent, subascending, the esi carina arcuate 
and decurrent; dorsal lobes obovate, .35-.85 mm. long, .27—.65 
mm. wide, nearly plane or slightly concave, экан longitudinally 
adnate to the stem, which the inner margin does not surpass, apex 
very obtusely rounded ; ventral lobes of the leaves on the younger 
ramuli subequal to the dorsal lobes or one half as large, those of 
the adult leaves one third the size of the dorsal, inflated, rhom- 
boidal-ovate, the obtuse or subacute apex more or less appressed 
to the dorsal lobe, the inner margin almost wholly adnate to the 
stem and scarcely incumbent, the outer margin obliquely truncate; 
leaf-cells 9-16и, the walls күү thickened at Ше angles: 
dioicous : androecia terminal on main stem or principal branches, 
numerous, linear, 3-7 mm. long, .5— Ж mm. wide, usually directed 
downward; 4 bracts 10-35 pairs, very closely imbricated, 
strongly ventricose, the lobes equal: Ф bracts of about the same 
size as the sie the lobes subequal: perianth obconic, 1.2-2 
mm. long, . 2 in greatest width, bilabiate, the lips entire : cap- 
sule prolate- "ellipsoidal, exserted 1-2 mm., the valves about 1 mm. 
long, transverse striae of the inner cells very obscure or wanting ; 
spores subglobose or ellipsoidal, 48—60 и in maximum diameter, 
minutely and densely echinulate-papillate ; elaters 150—200 м x 
6—8 p. 
On the trunks of trees (Alnus, Umbellularia, etc.). Com- 
mon in the Coast Range Mountaius—at least, from San Francisco 
northward ; Mill Valley, Marin Co.; Cazadero, Sonoma Co.; Men- 
docino (549); Eureka (918) and near McBride's, Mad River 
(1051), Humboldt Co. Vancouver Island (Macoun).* 
2. RADULA COMPLANATA (L.) Dumort. Comm. Bot. 112. 1822. 
Jungermannia complanata L. Sp. Pl. 1133. 1753. 
Mostly yellowish-green, rather flaccid, closely E. radially 
creeping, finally forming depressed mats: stems 1—6 cm. long, ir- 
regularly pinnate: leaves closely imbricate, patent, t the margins 
occasionally gemmiferous ; dorsal lobes quadrate-orbicular, .5— 
пе Prr 
* There seems to be little or th i's 
apparently wholly sterile Ааёша arctic (from Chlowak and Chilcoot, Alaska. — 
Bot. Jahrb, 8: 98. //. 3. f. гг. 1886) to distinguish it from the juvenile condition of 
Radula Bolanderi. À 
